Canadian Anaesthetists’ Society Journal

, Volume 27, Issue 5, pp 433–439 | Cite as

Mechanisms of anaesthesia: A review

  • Sheldon H. Roth


Anaesthesia is a drug-induced reversible perturbation of neuronal activity. Since a wide variety of structurally unrelated substances are capable of producing this phenomenon, it has been generally accepted that anaesthetics produce their effects through non-specific hydrophobic interactions. Results of recent studies in whole animal and cellular (membrane) preparations demonstrate that a unitary theory of action does not exist. Anaesthetics can produce a spectrum of activity in the central nervous system, and different agents produce different patterns of activity. At the cellular and membrane level, differential effects have been observed, structural dependent differences occur and optical isomers display very different activities. The perturbation (fluidity change) of membrane components does not appear to be uniform for all anaesthetics. It is concluded that anaesthetics are selective agents, and produce their effects at multiple sites and through a variety of mechanisms.


L’anesthésie est une perturbation réversible d’origine médicamenteuse de I’activité neurologique. Comme une grande variété de substances non apparentées structurellement peuvent produire ce phénomène, il est généralement accepté que les agents anesthésiques produisent leurs effets par des interactions non spécifiques à caractère hydrophobique. Les résultats de travaux récents, tant chez l’animal que ceux effectués sur des montages cellulaires (niveau de la membrane) ont démontré l’absence d’une théorie unique pour expliquer le mécanisme d’action des anesthésiques. Les anesthésiques peuvent exercer leur activité à plusieurs sites du systéme nerveux central et différents agents exercent des effets différents. Au niveau de la membrane et de la cellule, des effets différents ont été observes, on note des différences selon la structure moléculaire et des isomères optiques exercent des actions trés différentes. Les modifications (propriétés fluidiques) des composants de la membrane ne semblent pas uniformes avec tous les agents. On conclut que les agents anesthesiques sont des agents sélectifs qui produisent leurs effets é différents sites et par des mécanismes variés.


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Copyright information

© Canadian Anesthesiologists 1980

Authors and Affiliations

  • Sheldon H. Roth
    • 1
  1. 1.Division of Pharmacology and Therapeutics, Faculty of MedicineThe University of CalgaryCalgaryCanada

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